This invention relates to apparatus for use in mining or tunnelling installations.
Systems are known in which tunnels or headings are driven in rock with the protection of an advancing shield which accommodates a cutting machine and which is caused to follow up in the direction of advance. A permanent lining, for example a steel arch lining, a concrete lining or a brick lining, is introduced behind the advancing shield.
In known shield advancing apparatus, the shield usually has to be shifted as a constructional assembly together with the heavy cutting machinery accommodated therein and with the loading device, as well as the power unit. This necessitates considerable feed power. Moreover, the shield cannot be shifted until the cutting machine has opened up the face being cut, over its full cross-section, to a certain working depth. During the shield advancing operation the cutting work has to stop.
German Specification No. 1,921,314 describes a cutting machine, for underground mine workings, which consists of a frame stand with lining frames arranged side-by-side at a certain distance apart and capable of being shifted by a guiding and shifting device in the direction in which the work progresses. A slide serving as a carrier for a mining device, and displaceable in relation to the frames, is interposed between the latter. Apparatus of this kind is specially intended for the driving of tunnels of small rectangular cross-section. This system does not enable the cross-section of the excavation in the working zone to be screened off in a reliable way, particularly in the case of larger tunnels or headings.
The main aim of the invention is to provide a shield advancing apparatus, for driving headings or tunnels in rock, which is capable of being reliably advanced independently of the cutting machine contained therein.